Customer orientation has always been the most interest in the market. In recent years, mobile technology grows vastly to meet the facility need of common users. Wireless communication therefore becomes an important part in the trend. Among all wireless technologies, the infrared (IR) system is the most widely seen. From TV remote to security sensors, IR transmission has been implemented in different protocols for different purposes. Without any doubt, computer system also adopts IR transmission for transferring data or command. For example, IrDA (Infrared Data Association) and CIR (Consumer Infrared) are two of the commonly used IR transmission systems in a notebook computer. The IrDA transmission system allows wireless data transmission between a notebook computer and an external electronic device, e.g. another notebook computer. On the other hand, the CIR transmission system allows a notebook computer to be controlled via a remote controller. Conventionally, when a notebook computer exhibits both of these two transmission protocols, two independent transmission systems are used for executing data transmission and control command transmission respectively, as illustrated in FIG. 1. In the computer system 10, the IrDA transmission system is formed by the IrDA transceiver 101 and the IrDA module 102, and the CIR transmission system is formed by the CIR receiver 103 and CIR module 104. The IrDA transceiver 101 receives an external IrDA signal then transmits the IrDA signal to the IrDA module 102 for processing. Likewise, the CIR signal is received by the CIR receiver 103 and processed by the CIR module 104. Due to different characteristics of the two protocols, the computer system 10 must have two different mechanisms for processing signals of either kind.
For integration purpose, the two transmission systems can be integrated by having an IrDA module 211 and a CIR module 213 share the same I/O component, i.e. a common IR transceiver 212, as illustrated in FIG. 2. Under this circumstance, the IR transceiver 212 has to be able to receive the IR signal in frequencies of both protocols. But the IrDA module 211 and the CIR module 213 have to distinguish whether the IR signal is the desired input on their own. Moreover, since the IR transceiver 212 will transmit the received IR signal to both the IR modules 211 and 213 and apparently only one of the IR modules 211 and 213 can correctly decode the IR signal, the other one that fails to decode the IR signal will incur with physical errors. For example, if the IrDA module 211 can correctly decode the received IR signal, the CIR module 213 will fail to do that due to the different IR protocol the CIR module 213 is applied. As a result, the CIR module 213 may encounter physical errors and could not be able to decode subsequent IR signals unless an error recovery solution is applied.
For solving the physical error problem, the end user may need to determine which IR transmission system is working and thus switch to the IR module for the desired job. This implement is far from user-friendly requirements of modern electronic devices.